Ciliated protozoans:
(a) are aquatic, actively moving organisms
(b) have a cavity (gullet) that opens to the outside of the cell surface.
(c) cilia performs coordinated movement which causes the water laden with food to be steered into the gullet.

Ciliated protozoans are aquatic, actively moving organisms because of the presence of thousands of cilia. They have a cavity (gullet) that opens to the outside of the cell surface. The coordinated movement of rows of cilia causes the water laden with food to be steered into the gullet. Example: Paramoecium